Steve on Image Processing with MATLAB

Image processing concepts, algorithms, and MATLAB

The MATLAB community and me

As Ned Gulley posted over on the MATLAB Community blog last week, MATLAB Central is 15 years old.

Ned commented that MATLAB Central was “giving a modern web-based home to a community that was already thriving.” That reminded me of how important MathWorks participation in that community has been to me personally.

Many, many moons ago, as the calendar changed and 1992 became 1993, I was a fairly unhappy electrical engineering professor. I was thinking about changing my career path, but I didn’t have any solid ideas about what to do outside academia.

I was a heavy MATLAB user, so I immediately subscribed when the new Usenet group, comp.soft-sys.matlab, launched in January. I soon noticed when Cleve Moler, creator of the original MATLAB, posted a note from MathWorks:

Hi. This is the first posting from The MathWorks to comp.soft-sys.matlab. I’m posting it from Stanford because we’re having trouble posting to newly establish groups, including comp.soft-sys.matlab, from the MathWorks machines in Massachusetts. We can post to old, established groups, but not to some new ones, including what is now the most important group for us. If anybody else is having similar difficulties, please let us know. Thanks to Michael Maurer at Stanford for initiating the group. The size of the vote in favor, and the level of participation this first week, are certainly good signs for an active, useful group.

At the MathWorks, we intend to follow the group’s activities, to respond individually to technical and informational queries, and to post general responses and announcements when we believe they are of broad interest. We certainly intend to respect the Net’s noncommercial culture.

We hope that many of the queries will be answered by other group participants. The discussion we’ve seen so far of MATLAB/Unix memory management is a good example of how this ought to work.

Thanks to all of you for your support of MATLAB. With your help, comp.soft-sys.matlab can be a valuable, and enjoyable, activity for all of us.

– Cleve Moler
Chairman and Chief Scientist
The MathWorks

And Cleve kept posting, always eager to teach people how to get their mathemetical computations done accurately and efficiently. For example, this 30-Jan-1993 post was in response to a question about computing factorials in MATLAB:

MATLAB does not have a factorial function, so n! must be computed by

prod(1:n)

or, possibly with roundoff error, by

gamma(n+1)

But, be careful, either of these quantities overflow for n > 170. If you actually want n! to compute something like

n!/(k!*(n-k)!)

for large n, you should use

exp(sum(log(1:n))-sum(log(1:k))-sum(log(1:(n-k))))

It’s not as slow as it looks, and it doesn’t overflow.

– Cleve Moler

Then there was this fellow named John Little, who started posting on the same day as Cleve and who kept up a steady stream of technical MATLAB nuggets like this one:

The MEX-file facility in MATLAB 4.0 includes a new routine called mexPutMatrix that allows you to plop a matrix directly back into the MATLAB workspace.

John Little

(At MathWorks, we generally call him “Jack.” He is our CEO.)

I noticed other MathWorks people jumping in, too. Clay Thompson answered one of my own questions in early February 1993. And then there was Loren Shure, who was answering a question about the quad function in March 1993. (Many of you know Loren from her Art of MATLAB blog.)

By following these MathWorks interactions in the early MATLAB community, I began to form a very favorable impression of the company and the people who worked there. When I saw Loren at a signal processing conference that spring, I introduced myself, and I volunteered to be a beta tester for the new image processing product that Loren could only hint about. By the fall of 1993, I had participated in the beta test and then interviewed (successfully) for a job. My family and I moved from Chicago to Massachusetts in December, and we’ve been here ever since!

|
  • print

Comments

To leave a comment, please click here to sign in to your MathWorks Account or create a new one.